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1.
South Asian J Cancer ; 5(4): 167-175, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28032079

RESUMEN

The Oncology Gold Standard (OGS) Expert Group on renal cell carcinoma (RCC) developed the consensus statement to provide community oncologists practical guidelines on the management of advanced clear cell (cc) RCC using published evidence, practical experience of experts in real life management, and results of a nationwide survey involving 144 health-care professionals. Six broad question categories containing 33 unique questions cover major situations in the routine management of RCC. This document serves as a ready guide for the standard of care to optimize outcome. The table of "Take Home Messages" at the end is a convenient tool for busy practitioners.

2.
Ann Oncol ; 24(2): 329-336, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23104724

RESUMEN

BACKGROUND: Intetumumab is a fully human mAb with antiangiogenic, antitumor properties which has shown potential therapeutic effect in castration-resistant prostate cancer (CRPC) patients. PATIENTS AND METHODS: In a phase 2, randomized, double-blind, multicenter study, men with metastatic CRPC without prior systemic nonhormonal therapy were randomly assigned to 75-mg/m(2) docetaxel (Taxotere) and 5-mg prednisone plus placebo (N = 65) or 10-mg/kg intetumumab (N = 66) q3w. Placebo patients with progressive disease (PD) could cross over to 10-mg/kg intetumumab alone or with docetaxel. The primary end-point was progression-free survival (PFS). The secondary end-points included tumor response (complete response + partial response, CR + PR), prostate-specific antigen (PSA) response, and overall survival (OS). RESULTS: All efficacy end-points favored placebo over intetumumab, including PFS (median 11.0 versus 7.6 months, P = 0.014), tumor response (20% versus 16%, P = 0.795), PSA response (68% versus 47%, P = 0.018), OS (median 20.6 versus 17.2 months, P = 0.163). Common all-grade adverse events (AEs) with placebo and intetumumab were alopecia (43% versus 26%); diarrhea, leukopenia (both 34% versus 27%); neutropenia (35% versus 23%). Grade ≥ 3 leukopenia (28% versus 17%) and neutropenia (26% versus 18%) occurred more often with placebo than with intetumumab. Intetumumab serum concentrations increased with repeated dosing and did not reach steady-state. Greater decreases in N-telopeptide of type I collagen (NTx), C-telopeptide (CTx) and CTCs occurred with intetumumab than with placebo. CONCLUSION: The addition of intetumumab to docetaxel resulted in shorter PFS without additional toxicity among CRPC patients.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Integrina alfaV/inmunología , Prednisona/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Taxoides/uso terapéutico , Anciano , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Supervivencia sin Enfermedad , Docetaxel , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/tratamiento farmacológico , Orquiectomía , Placebos/administración & dosificación , Prednisona/efectos adversos , Neoplasias de la Próstata/mortalidad , Sobrevida , Taxoides/efectos adversos
3.
Plant Cell Rep ; 30(12): 2215-31, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21847621

RESUMEN

cDNA and genomic clones of cinnamoyl CoA reductase measuring 1011 and 2992 bp were isolated from a leguminous pulpwood tree Leucaena leucocephala, named as LlCCR. The cDNA exhibited 80-85% homology both at the nucleotide and amino acid levels with other known sequences. The genomic sequence contained five exons and four introns. Sense and antisense constructs of LlCCR were introduced in tobacco plants to up and down-regulate this key enzyme of lignification. The primary transformants showed a good correlation between CCR transcript levels and its activity. Most of the CCR down-regulated lines displayed stunted growth and development, wrinkled leaves and delayed senescence. These lines accumulated unusual phenolics like ferulic and sinapic acids in cell wall. Histochemical staining suggested reduction in aldehyde units and increased syringyl over guaiacyl (S/G) ratio of lignin. Anatomical studies showed thin walled, elongated xylem fibres, collapsed vessels with drastic reduction of secondary xylem. The transmission electron microscopic studies revealed modification of ultrastructure and topochemical distribution of wall polysaccharides and lignin in the xylem fibres. CCR down-regulated lines showed increased thickness of secondary wall layers and poor lignification of S2 and S3 wall layers. The severely down-regulated line AS17 exhibited 24.7% reduction of Klason lignin with an increase of 15% holocellulose content. Contrarily, the CCR up-regulated lines exhibited robust growth, development and significant increase in lignin content. The altered lignin profiles observed in transgenic tobacco lines support a role for CCR down-regulation in improving wood properties of L. leucocephala exclusively used in the pulp and paper industry of India.


Asunto(s)
Aldehído Oxidorreductasas/metabolismo , Fabaceae/enzimología , Lignina/análisis , Fenoles/análisis , Proteínas de Plantas/metabolismo , Aldehído Oxidorreductasas/genética , Celulosa/análisis , Celulosa/metabolismo , ADN Complementario/genética , ADN de Plantas/genética , Regulación hacia Abajo , Fabaceae/genética , Regulación de la Expresión Génica de las Plantas , Lignina/metabolismo , Microscopía Electrónica de Transmisión , Fenoles/metabolismo , Fenotipo , Proteínas de Plantas/genética , Tallos de la Planta/anatomía & histología , Tallos de la Planta/ultraestructura , Plantas Modificadas Genéticamente/genética , Nicotiana/química , Nicotiana/genética , Transformación Genética
4.
J Mol Model ; 15(2): 203-21, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19048314

RESUMEN

Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) is an important enzyme that participates in lignin biosynthesis especially in the formation of cell wall ferulic esters of plants. It plays a pivotal role in the methylation of the 3-hydroxyl group of caffeoyl CoA. Two cDNA clones that code CCoAOMT were isolated earlier from subabul and in the present study; 3D models of CCoAOMT1 and CCoAOMT2 enzymes were built using the MODELLER7v7 software to find out the substrate binding sites. These two proteins differed only in two amino acids and may have little or no functional redundancy. Refined models of the proteins were obtained after energy minimization and molecular dynamics in a solvated water layer. The models were further assessed by PROCHECK, WHATCHECK, Verify_3D and ERRAT programs and the results indicated that these models are reliable for further active site and docking analysis. The refined models showed that the two proteins have 9 and 10 alpha-helices, 6 and 7 beta-sheets respectively. The models were used for docking the substrates CoA, SAM, SAH, caffeoyl CoA, feruloyl CoA, 5-hydroxy feruloyl CoA and sinapyl CoA which showed that CoA and caffeoyl CoA are binding with high affinity with the enzymes in the presence and absence of SAM. It appears therefore that caffeoyl CoA is the substrate for both the isoenzymes. The results also indicated that CoA and caffeoyl CoA are binding with higher affinity to CCoAOMT2 than CCoAOMT1. Therefore, CCoAOMT2 conformation is thought to be the active form that exists in subabul. Docking studies indicated that conserved active site residues Met58, Thr60, Val63, Glu82, Gly84, Ser90, Asp160, Asp162, Thr169, Asn191 and Arg203 in CCoAOMT1 and CCoAOMT2 enzymes create the positive charge to balance the negatively charged caffeoyl CoA and play an important role in maintaining a functional conformation and are directly involved in donor-substrate binding.


Asunto(s)
Fabaceae/enzimología , Metiltransferasas/química , Modelos Moleculares , Proteínas de Plantas/química , Secuencia de Aminoácidos , Dominio Catalítico , Coenzima A/química , Simulación por Computador , Isoenzimas/química , Isoenzimas/clasificación , Metiltransferasas/clasificación , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/clasificación , Estructura Secundaria de Proteína , Programas Informáticos , Homología Estructural de Proteína , Especificidad por Sustrato
5.
FEMS Microbiol Lett ; 242(1): 13-8, 2005 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-15621415

RESUMEN

An approximately 4.9 kb Sau3A I genomic DNA fragment from the Streptomyces aureofaciens NRRL 2209 aiding in the biosynthesis of PHB in recombinant Escherichia coli has been sequenced and analysed for phaC gene. The putative phaC(Sa) gene of 2 kb is 79.1% GC rich and encodes a 63.5 kDa protein. It expressed under its own promoter and significant PHA synthase activity was detected in the recombinant E. coli. This is the first putative PHA synthase gene reported from a Streptomyces sp. with serine as the active nucleophile in the conserved lipase box. The phaC(Sa) was found in close proximity to a regulatory gene, which apparently regulated the phaC expression.


Asunto(s)
Aciltransferasas/genética , Aciltransferasas/metabolismo , Streptomyces aureofaciens/enzimología , Secuencias de Aminoácidos/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Composición de Base , Cromosomas Bacterianos/genética , Clonación Molecular , ADN Bacteriano/química , Escherichia coli/genética , Escherichia coli/metabolismo , Genes Bacterianos , Genes Reguladores , Datos de Secuencia Molecular , Peso Molecular , Sistemas de Lectura Abierta , Regiones Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análisis de Secuencia de ADN , Serina/genética , Streptomyces aureofaciens/genética
6.
Microbiol Res ; 158(1): 19-27, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12608576

RESUMEN

Recombinant Escherichia coli (ATCC:PTA-1579) harbouring poly(3-hydroxybutyrate) (PHB) synthesising genes from Streptomyces aureofaciens NRRL 2209 accumulates PHB. Effects of different carbon and nitrogen sources on PHB accumulation by recombinant E. coli were studied. Among the carbon sources used glycerol, glucose, palm oil and ethanol supported PHB accumulation. No PHB accumulated in recombinant cells when sucrose or molasses were used as carbon source. Yeast extract, peptone, a combination of yeast extract and peptone, and corn steep liquor were used as nitrogen sources. The maximum PHB accumulation (60% of cell dry weight) was measured after 48 h of cell growth at 37 degrees C in a medium with glycerol as the sole carbon source, and yeast extract and peptone as nitrogen sources. Scanning electron microscopy of the PHB granules isolated from recombinant E. coli revealed these to be spherical in shape with a diameter ranging from 0.11 to 0.35 pm with the mean value of 0.23 +/- 0.06 pm.


Asunto(s)
Proteínas Bacterianas/genética , Carbono/farmacología , Escherichia coli/metabolismo , Hidroxibutiratos/metabolismo , Nitrógeno/farmacología , Poliésteres/metabolismo , Streptomyces aureofaciens/genética , Aciltransferasas/genética , Aciltransferasas/metabolismo , Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/ultraestructura , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular
7.
Int J Biol Macromol ; 31(1-3): 63-9, 2002 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-12559428

RESUMEN

An approximately 5.0 kb Sau3A I genomic DNA fragment from Streptomyces aureofaciens NRRL 2209 was cloned in a plasmid vector and introduced into Escherichia coli. The recombinant E. coli accumulated polyhydroxyalkanoates (PHAs) as cytoplasmic inclusions. The accumulated PHA was identified as the isotactic homopolymer of PHB with a molecular weight of 2.85x10(5). Purified PHB granules were spherical with an average size of 1.1 microm and of stable configuration. DSC thermogram suggested high crystalline nature of the polymer. Maximum thermal degradation of the biopolymer occurred between 250 and 340 degrees C. Recombinant E. coli cells preferentially utilized glycerol as the carbon source and accumulated 25-28 times more PHB than the native S. aureofaciens.


Asunto(s)
Ácidos Carboxílicos/química , ADN/genética , Escherichia coli/metabolismo , Streptomyces aureofaciens/metabolismo , Rastreo Diferencial de Calorimetría , Carbono/metabolismo , Cromatografía de Gases , Clonación Molecular , Vectores Genéticos , Glicerol/metabolismo , Espectroscopía de Resonancia Magnética , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Modelos Químicos , Plásmidos/metabolismo , Plásticos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
8.
Indian J Exp Biol ; 40(5): 624-7, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12622216

RESUMEN

Immature zygotic embryo explants of Carica papaya were cultured on MS medium supplemented with 2,4-D (2.0 mg/l) and formed globular embryos on explants without callus formation in 4-6 weeks. Maturation and conversion of somatic embryos was also achieved on the same medium. Cotyledonary stage embryos germinated to 63.66 and 68.33% in cv. honey dew and washington respectively in MS basal medium supplemented ABA (0.5 microm/l). Robust development and proliferation of plantlet roots in vitro was obtained on MS basal medium. Hardened plantlets have 60% survival rate.


Asunto(s)
Carica/embriología , Semillas/crecimiento & desarrollo , Carica/crecimiento & desarrollo , Medios de Cultivo , Regeneración
9.
Biochim Biophys Acta ; 1381(1): 104-12, 1998 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-9659377

RESUMEN

Taxol is perhaps the most successful drug used for the treatment of various cancers. Comprehensive literature accumulated on therapeutics of the drug has indicated numerous side effects. In this paper, by use of fluorescence spectroscopy, it is shown that taxol binds to DNA with an affinity constant (Ka) of 1.08 x 10(7) M-1. This binding is accompanied by a large 'red edge excitation shift' (REES) of fluorescence emission maximum in taxol-DNA complex. The results point to an interaction of taxol with its core eight-membered ring in the DNA groove and the three phenyl rings projecting away from the DNA. The drug encompasses about two base pairs of DNA upon binding to it. Systematic studies with taxol analogues confirms such a mode of binding. These interesting findings on hitherto unknown taxol-DNA interactions may have clinical implications in view of its large number of side effects and pharmacokinetics.


Asunto(s)
Antineoplásicos Fitogénicos/metabolismo , ADN/metabolismo , Paclitaxel/metabolismo , Dicroismo Circular , ADN/biosíntesis , ADN/química , Espectrometría de Fluorescencia
10.
J Plant Physiol ; 117(1): 7-15, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23195498

RESUMEN

The developmental patterns of the nitrogen assimilating enzymes were investigated and compared in the non-shoot forming and the shoot forming callus cultures of sugarane. In the shoot forming tissue the pre-emergence period od shoots was characterised by increasing activities of glutamine synthetase and glutamate synthase. The activity of these enzymes during the corresponding period in the non-shoot forming callus was found to decline. Although the activity of glutamate dehydrogenase in the shoot forming callus during the period of pre-emergence of shoots did not show any appreciable change, in the non-shoot forming callus, it increased during the corresponding period. The developmental patterns of nitrate reductase in both the programmes were identical except for the fact that in the shoot forming tissue the nitrate reductase activity was higher at all times than in the non-shoot forming callus. The data suggest that (a) shoot differentiation occurs concomitant with peak glutamine synthetase, glutamate synthase, and nitrate reductase activity, whereas the glutamate dehydrogenase activity is at its lowest, (b) better mobilization of nitrate occurs in the shoot forming callus and (c) the glutamine synthetase/glutamate synthase pathway becomes operative prior to shoot differentiation.

11.
Plant Cell Rep ; 3(4): 138-41, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24253470

RESUMEN

The in vivo nitrate reductase activity in 8 day old dark-grown sugarcane callus was over three fold that of the light-grown callus. NADH (0.3 mM) in the reaction system, increased the in vivo nitrate reductase activity by more than two fold both in the dark- and the light-grown callus tissues. The NADH dependence of nitrate reductase activity followed Michaelian kinetics. The apparent Km values for NADH were 0.083 mM and 0.20 mM, respectively, for the dark- and the light-grown callus. In vivo nitrate reductase activity in green sugarcane leaves (field grown) was unaffected by NADH in the reaction system. Under the standard conditions of assay up to 60% of the NADH penetrated into the sugarcane callus within 2 min. No penetration of NADH into the sugarcane leaf discs was, however, recorded under identical conditions.

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